Plane expansible corrugations



Oct. 18, 1966' 5 Sheets-Sheet 1 Filed May 20, 1963 I Oct. 18, 1966 c ARNE 3,279,973

PLANE EXPANS I BLE GORRUGAT IONS Filed May 20, 1963 3 Sheets-Sheet 2 Oct. 18, 1966 CARNE PLANE EXPANSIBLE CORRUGATIONS 5 Sheets-Sheet 3 Filed May 20, 19 3 1 (lb/1e United rates Patent 3,279,973 PLANE EXPANSIBLE CORRUGATIONS Christian Arne, 2203 N. Nordica Ave., Chicago, Ill. Filed May 20, 1963, Ser. No. 281,718 4 Claims. (Cl. 161-131) My invention relates to a new geometrical form that will find wide application as a structure expansible in all directions. In particular, my invention involves a substantially plane expandably corrugated surface.

Controlling the expansion of materials has long been a problem in many industries. Among-the methods developed to combat the problem was that of working the material into longitudinal corrugations transverse to the direction of expansion and contraction. Although the conventional longitudinal corrugations of this nature had much success, structures fabricated from such longitudinally corrugated materials can expand only along an axis transverse to the corrugations.

I have designed a form of surface which will allow a product to expand with cumulative bellows action in all directions along the general surface of the material. The term expansion as hereafter used implies both an expanding and contracting action. The structure may include isolated substantially non-deformed units, but the major action of expansion takes place by providing in the surface of the material expansion units. This form is called plane expandable corrugations.

The structure of the present invention is a surface in which corrugations are so formed and so located that the surface can expand in every direction by flexing across the corrugations. Patterns of corrugations are formed in individual expansion elements composed of an extending or depending conical element, each element expansible in itself. The elements are located over the surface in interlinked configuration so that the borderline between adjacent units approximates a closed loop. The surface is therefore also described as being covered with a plurality of tangentially connected loops.

Plane expansible corrugations will find great use in the manufacture of building materials, such as in non-warping roofing sheets, resilient floor slabs, forms for concrete work and expansion sections in steam pipes. It is important to note that due to the regular configuration of the plane expandable corrugation, individual sections may be easily joined together by nesting one in the other. This quality makes the plane expansible corrugation easily adaptable for use as a sealing material in floating roof tanks and as a flexible curtain in variable volume tanks. The invention is also adaptable as the accordian attachment between railroad cars.

Possibly the greatest application of plane expansible corrugations will be to the metal foil and paper towel field. Besides being able to expand over large and irregular surfaces without tearing, the plane expansible co-rrugation will lend itself to the convenient sealing of the package or item to be wrapped.

Being a new geometrical form, plane expansible corrugations will find wideacceptance because of its ornamentation qualities, whether or not its qualities in building materials or expandable structures are utilized or recognized.

Further objects and advantages, of the present invention will be apparent from the following description, reference being had to the accompanying drawing wherein:

FIGURE 1 is a fragmentary view of a structure including plane expansible corrugations;

FIGURE 2 is a sectional view as taken along line 22 of FIGURE 1;

FIGURE 3 is a cross-section of one of the units formed in the surface;

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FIGURE 4 is an alternative embodiment of the present invention;

FIGURE 5 is a representation of the tangential loops existing at the datum plane;

FIGURE 6 is a representation of the tangential loops in the datum plane after the structure has been expanded;

FIGURE 7 is an alternative embodiment of the present invention;

FIGURE 8 is a sectional view taken along line 8--8 of FIGURE 7;

FIGURE 9 is an isometric view of the present invention;

FIGURE 10 is a sectional elevation of a specific embodiment of the present invention;

FIGURE 11 is a sectional view as taken along line 11-11 of FIGURE 10;

FIGURE 12 is a fragmentary view of an alternative structure including plane expansible corrugations;

FIGURE 13 is a plan view of an alternative embodiment of the present invention; and

FIGURE 14 is a plan view of an alternative embodiment of the present invention.

In an illustrative embodiment of the present invention, and referring first .to FIGURES 1, 2 and 9, alternating extending 11 and depending 12 hollow frusto conical elements are formed in the datum plane 10 of the material and are arranged in a plurality of hexagonal groupings 14. The terms extending and depending refer to similar conical elements but on opposite sides of the datum plane 10. Each hexagonal grouping 14 of frusto conical elements encloses a substantially non-deformed unit 16 in the datum plane 10. Each extending 11 frusto conical element is therefore surrounded by three depending 12 frusto conical elements and three substantially non-deformed units 16.

The sidewalls 18 of the extending 11 and depending 12 frusto conical elements are common sidewalls 18 in which corrugations 21 have been formed. The corrugations 21 of each extending 11 and depending 12-frusto conical element extend from the frustum 23 of the extending 11 or depending 12 frusto conical element, along the common sidewalls 18 to the datum plane 10 where they merge with the corrugations 21 extending along the adjacent extending 11 or depending 12 frusto conical element.

As can be seen in FIGURE 1, and more clearly in FIGURE 5, each frusto conical element describes a closed loop 24 at the datum plane 10. Because the alternating extending 11 and depending 12 frusto conical elements share common sidewalls 18, these closed loops 24 appear tangent to each other in the datum plane 10.

Expansion occurs in each individual extending 11 and depending 12 frusto conical element evidenced by a shallowing of the element, i.e, the frustum 23 approaches the datum plane 10, and the closed loops 24 are deformed. The deformation of the closed loops 24 is shown in FIGURE 6, wherein an elliptical shape is approximated when the force exerted on the material is not uniform in all directions.

A cross-section of an extending 11 or depending 12 hollow conical element is shown in FIGURE 3, enabling further illustration of the corrugations 21.

In an alternative embodiment of the present invention, and referring specifically to FIGURE 4, the extending 11 and depending 1 2 hollow conical elements extend to an apex 26 rather than to a frustum 23. In this embodiment the corrugations 21 extend from the apex 26 along the common sidewalls 18 to the datum plane 10 where they join the corrugations 21 extending along the common sidewall 18 of the adjacent conical element.

As shown in FIGURE 12, the alternating extending 11 and depending 12 frusto conical elements are grouped in a four-sided pattern. Each individual pattern would therefore consist of two corrugated extending elements 11, two corrugated depending elements 12 and an enclosed, substantially non-deformed unit 16 in the datum plane 10. This four-sided pattern is particularly applicable in expansion joints for pipes and pipe systems wherein the expansion is generally either along the pipe axis or perpendicular to the pipe axis. When a pipe is stretched, the axial length increases while the circumference of the pipe normally decreases. When using plane expansible corrugations of the four-sided pattern, the sides perpendicular to the pipe axis will separate while the sides parallel to the axis will be drawn together. As was shown in FIGURE 6, the closed tangential loop 24 at the datum plane Will take on an elliptical configuration with the transverse axis parallel to the pipe axis.

FIGURES 7 and 8 illustrate an alternative method of corrugating the sidewalls 13 of the extending 11 and depending 12 hollow conical elements. The corrugations 25 extend both along 31 and diagonally across 32 the sidewalls 18 from one conical element to the next.

In another embodiment of the present invention, the expansible corrugations 5 are formed in only a portion of the surface of the material. The corrugations 21 can be placed on the surface in a strategic manner to control the expansion or contraction as is desired. In this manner, rigidity and flexibility can be combined. An example of such an application would be in the construction of a storage tank 40, as shown in FIGURES l and 11, wherein the diameter of such tanks 40 frequently exceed 100 feet. The tank floor 41 is provided with a belt 42 of plane expandable corrugations around its outer periphery. The floor 41 is then able to expand while maintaining a solid foundation.

In the construction of a cryogenic storage tank 40 having a 100 foot diameter it is necessary to compensate for a vast temperature change. Such a tank 40 may be built at an outdoor temperature of approximately 60 F. and is expected to contain liquids at 40 F. Assuming the coefiicient of expansion of aluminum to be 2X10 inches/degree, the radial thermal deformation could be expected to be at least 1.2 inches /2 diameter X100 X2 1O- Using a tank floor 41 with a foot belt 42 of expansible corrugations of the hexagonal type, the entire deformation would easily be absorbed.

Where the structure, by necessity, is to be constructed of numerous plates welded together, it may be preferred to place the plane expansible corrugations 5 as shown in FIGURE 13. The edges 51 of the plate 50 would then be uniform and adaptable to welding.

Where the plate 50 is to be nested with another plate, or is to be employed individually, the embodiment of FIGURE 14 is preferred. The plane expansible corrugations 5 are situated along the edge 51 of the plate 50.

In still another alternative embodiment of the present invention, the extending 11 and depending 12 frusto conical elements are of a varying distance from the datum plane 10. The frustum 23 or apex 26 of the extending 11 elements may be of a greater or lesser distance from the datum plane 10 than the frustum 23 or apex 26 of the depending 12 elements. The frustum. 23 or apexes 26 of the extending 11 elements may be equidistant from the datum plane 10 whereas the frustum 23 and apexes 26 of the depending 12 elements may be of varying distance.

Such alternative arrangements may be necessary to accommodate adjacent bodies and members or to provide a more stable base or structure.

Plane expansible corrugations can be formed in virtually all materials of construction. Preformed concrete, steel columns and aluminum sheeting are obvious examples. Wrapping materials such as aluminum. foil, tin foil and paper towels find increased utility when provided with plane expandable corrugations.

Plane expansible corrugations may be formed in the surface of structures of virtually any configuration including, but not limited to, planes, cones, spheres, cylinders or hyperboloids.

The thickness requirements of the material generally need not be altered because of the use of plane expandable corrugations. Load requirements remain the basic factor for determining thickness.

The foregoing detailed description has been given for clearness of understanding only, no unnecessary limitations implied, as modifications will be obvious to those skilled in the art.

What is claimed is:

1. A sheet expansible in all directions comprising:

a single sheet of a plurality of hollow conical elements have been formed in a predetermined pattern in the surface thereof;

said conical elements alternately extending from and depending from a common datum plane;

the adjacent extending and depending hollow conical elements having common sidewalls and forming points of tangency at the datum plane;

said adjacent extending and depending hollow conical elements enclosing substantially non-deformed units in the datum plane;

and said sidewalls of the hollow conical elements being corrugated.

2. The structure as described in claim 1 wherein said hollow conical elements extend and depend an equal distance from the datum plane.

3. A sheet expansible in all directions comprising:

single sheet of a plurality of hollow conical elements have been formed and define a continuous plurality of hexagonal groupings;

said elements alternately extending from and depending from a common datum plane;

the adjacent extending and depending conical elements having common sidewalls and forming points of tangency at the datum plane;

each hexagonal grouping enclosing a substantially nondeformed unit in the datum plane;

and said sidewalls of the conical elements being corrugated.

4. The structure as described in claim 3 wherein said hollow conical elements extend and depend an equal distance from the datum plane.

References Cited by the Examiner UNITED STATES PATENTS 2,275,575 3/1942 VIOOman l6l130 2,549,189 4/1951 Ga'bo l8934 X FOREIGN PATENTS 150,122 2/ 1953 Australia. 709,279 5/1954 Great Britain.

ALEXANDER WYMAN, Primary Examiner.

MORRIS SUSSMAN, Examiner. 

1. A SHEET EXPANSIBLE IN ALL DIRECTIONS COMPRISING: A SINGLE SHEET OF A PLURALITY OF HOLLOW CONICAL ELEMENTS HAVE BEEN FORMED IN A PREDETERMINED PATTERN IN THE SURFACE THEREOF; SAID CONICAL ELEMENTS ALTERNATELY EXTENDING FROM AND DEPENDING FROM A COMMON DATUM PLANE; THE ADJACENT EXTENDING AND DEPENDING HOLLOW CONICAL ELEMENTS HAVING COMMON SIDEWALLS AND FORMING POINTS OF TANGENCY AT THE DATUM PLANE; 